Carry her in your arms, and pretend you'll throw her in the swimming pool... She'll scream and hit you, but secretly she'll love it. Hold her hand while you talk. Hold her hand while you drive. Simply hold her hand. Tell her she looks pretty. Look into her eyes while you talk to her. Protect her. Tell her stupid jokes. Tickle her, even if she tells you to stop. When she starts cursing at you, tell her you love her. Let her fall asleep in your arms. Make her mad, then kiss her. Tease her. Let her tease you back. Kiss her cheek. Kiss her forehead. Just kiss her. Let her wear your clothes. Go slow. Don't force anything, and when you fall in love with her, tell her.
*Stolen from a friend's Facebook page